textproduct: Quad Cities

KEY MESSAGES

- As of 9 PM, the last of the isolated to scattered storms will be ending in southern Putnam County, with a quiet night to follow.

- A pattern change this weekend will bring heat and humidity to the area. The probability of heat headlines next week has increased to over 50%.

UPDATE

Issued at 856 PM CDT Wed Jun 24 2026

As expected, the weak mid level lapse rates and weak low level winds helped keep the severe weather threat isolated, as well as coverage of any storm this evening. The surface trof is now exiting the eastern CWA with the storms ending in the next half hour in southern Putnam county. I cleared the remaining watch counties this past hour.

SHORT TERM /THROUGH THURSDAY/

Issued at 224 PM CDT Wed Jun 24 2026

Satellite through early afternoon shows mainly diurnal cumulus across the area. Better cumulus is located across southwest Wisconsin where lapse rates are steeper and the better radar returns are located.

The cool front with a pre-frontal trof will slowly move through the area this afternoon/tonight. CAMs are struggling with the weak forcing but suggest isolated to low end scattered (10-30%) developing along the pre-frontal trof and cold front this afternoon evening.

The steep lapse rates and fairly straight hodographs suggest the primary risk this afternoon/evening is hail but a localized damaging wind and isolated tornado cannot be ruled out.

Based on progged destabilization, areas mainly east of the Mississippi and north of I-80 are favored for strong to severe storms through sunset.

Storms will dissipate with sunset leaving mainly dry conditions overnight,

LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/

Issued at 224 PM CDT Wed Jun 24 2026

Thursday night through Saturday night Assessment...low to medium (25-40%) confidence on rain

Another system will pass mainly south of the area Thursday night into Friday. Some solutions are further north. However, there is a large area ahead of the system with dry easterly flow. Thus there is a reasonably good chance the system will be either; 1) forced further south or 2) have a very sharp northern gradient to any rain.

Based on the AIGFS and ECMWF-AIFS and some ML progs, areas north of I-80 look to remain dry Thursday night and Friday. Along and south of I-80 there will be a risk of rain but the better chances still look to be south of an Ottumwa, IA to Galesburg, IL line. Even in this area, rainfall amounts will be around 0.10 inches.

Sunday through Wednesday Assessment...a certainty (>95%) of hot and humid conditions

The heat and humidity will tease the southwest half of the area on Sunday as dew points rise. The model consensus is probably raising dew points too quickly on Sunday, but, dew points of 65 to 70 are very reasonable.

Sunday night through Monday will be dry as the main storm track is well north of the area. Dew points of 70 to 75 are likely to be seen which will push heat indices above 100. The current probability of heat headlines for Monday is over 50 percent now.

Monday night into Tuesday the heat and humidity will continue with a 33-40% chance that heat headlines will be needed. However, a system in the Plains will develop a nocturnal storm complex that will track generally east northeast.

Data suggests a majority of the area will remain dry as the upper high in the Ohio Valley looks to remain in place through Tuesday. Parts of the far north and northwest have a 20-25% probability of seeing some rain if outflow from the storm complex can initiate some isolated convection.

Tuesday night into Wednesday becomes more of a question. The upper high over the Ohio Valley is progged to move closer to the east coast by several solutions. IF correct, this would help weaken the western parts of the heat dome and potentially allow the organized storm track to shift further south.

With several solutions indicating a shifting of the upper high toward the east coast, the model consensus does have a southward shift to the organized storm track. The net result is 20-30% rain chances late Tuesday night into Wednesday.

PWATS in the model solutions continue to be 1.5 inches or higher. Thus if storms do develop and move across the area, heavy rain can be expected.

AVIATION /00Z TAFS THROUGH 00Z THURSDAY/

Issued at 617 PM CDT Wed Jun 24 2026

The isolated thunderstorms along a cold front, have moved east of all TAF sites as of 6 PM. This will leave the area temporarily with gusty west winds, but by 01Z, a quick transition to light northwest winds is expected. Mainly VFR / clear skies can be expected tonight, with some patchy mid and high clouds passing through. Tomorrow, another wave of energy is expected to bring rain to areas south of Iowa. There is some low chance around 20-30 % that the rain could extend north into Highway 34 and north, but for now, I've left this out of TAFs.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.